Process for producing highly pure terephthalic acid
US4772748A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1986 |
| Grant date | Sep 20, 1988 |
| Priority date | — |
| Expiry date | Mar 31, 2006 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/265
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Disclosed herein is a process for producing highly pure terephthalic acid which forms polyesters of a particularly favorable color tone, the process comprising the steps of PA0 oxidizing p-xylene, thereby obtaining a mixture containing terephthalic acid, PA0 subsequently further oxidizing the thus obtained mixture at not higher temperature than that of the first oxidation step, PA0 still further oxidizing the reaction mixture of the second oxidation step at a higher temperature than that of the first oxidation step and PA0 treating the reaction mixture obtained by the third step of oxidation by bringing thereof into contact with molecular oxygen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.